• Title/Summary/Keyword: Brightness value

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A Study on Preprocessing Technique for Fingerprint Recognition using Applied Slit-Sum Method (Slit-Sum 방법을 응용한 지문인식 전처리 기술 연구)

  • 임철수;조성원
    • The Journal of the Korea Contents Association
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    • v.2 no.4
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    • pp.46-50
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    • 2002
  • This paper suggests the adaptive binary method which applies advanced silt sum technique, so that threshold value can be changed heuristically according to the brightness of captured fingerprint image. Through this research, we tried to resolve threshold value setting issue by the local differences of brightness of fingerprint image in the binary image preprocessing. The experimental results show that our proposed preprocessing method demonstrates the better recognition accuracy and can be applied to minutiae extraction algorithm for fingerprint recognition system.

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Impact of Residual Extractives in Kraft Pulps on Brightness and Color

  • Shin, Soo-Jeong;Sung, Yong-Joo;Park, Jong-Moon;Cho, Nam-Seok
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.41 no.5
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    • pp.20-25
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    • 2009
  • Residual extractives had a noticeable impact on the brightness of unbleached hardwood kraft pulps (trembling aspen). The brightness-impacting extractives were effectively removed by oxygen delignification. In addition, oxygen delignification was more effective in removing chromophores in hardwood unbleached kraft pulps than in those of softwood (loblolly pine). The residual extractives in unbleached hardwood kraft pulps also affected the pulp color, primarily redness and the L value. These redness-related extractives in unbleached hardwood kraft pulps were also effectively removed by oxygen delignification. There were no significant color differences between untreated and solvent-extracted oxygen-delignified aspen kraft pulps. The residual extractives in unbleached and oxygen-delignified softwood (loblolly pine) kraft pulps did not have a significant impact on either brightness or pulp color.

The Brightness Change of Fractured Surface in Accordance with Inclusion Contents of Magnesium Alloy (마그네슘합금내 개재물 함유량에 따른 파단면의 명도변화)

  • Kim, Hyun Sik;Ye, Dea Hee;Kang, Min Cheol;Kim, Jung Dae;Jeong, Hae Yong
    • Journal of Korea Foundry Society
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    • v.34 no.6
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    • pp.200-213
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    • 2014
  • Pure magnesium and magnesium alloys have been applied to various kinds of industrial fields, especially automotive and electronic parts. These parts are manufactured mainly through a diecasting process. These days, magnesium ingots are used as raw material, and recycled ingots are often used for commercial purposes. But the quality of virgin magnesium and recycled ingots is not secure. Therefore, massive casting defects can occur, and some things manufactured can be damaged by these defects. This study evaluated the inclusions of virgin magnesium and recycled ingot. It also included composition analysis by spectrometer, measuring inclusion contents by SEM & EDS, and performing a brightness test on fractured surfaces. The brightness test is generally very easy and obtains results quickly, so its results have been compared with the results obtained from various test methods. From the test results, we obtained a satisfactory result in evaluating inclusion and oxide. The brightness values are lower as the inclusion contents are higher. When the brightness value is over 47 in AM50A and 44 in AZ91D, the mechanical properties are expected to be good.

Welding Bead Detection Inspection Using the Brightness Value of Vertical and Horizontal Direction (수직 및 수평 방향의 밝깃값을 이용한 용접 비드 검출 검사)

  • Jae Eun Lee;Jong-Nam Kim
    • Journal of the Institute of Convergence Signal Processing
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    • v.23 no.4
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    • pp.241-248
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    • 2022
  • Shear Reinforcement of Dual Anchorage(SRD) is used to reinforce the safety of reinforced concrete structures at construction sites. Welding is used to make shear reinforcement, and welding plays an important role in determining productivity and competitiveness of products. Therefore, a weld bead detection inspection is required. In this paper, we suggest an algorithm for inspecting welding beads using image data of welding beads. First, the proposed algorithm calculates a brightness value in a vertical direction in an image, and then divides a welding bead in a vertical direction by finding a position corresponding to a 50% height point of the brightness value distribution in the image. The welding bead area is also divided in the same way for the horizontal direction, and then the segmentation image is analyzed if there is a welding bead. The proposed algorithm reduced the amount of computation by performing analysis after specifying the region of interest. In addition, accuracy could be improved by using all brightness values in the vertical and horizontal directions using the difference of brightness between the base metal and the welding bead region in the SRD image. The experiment compared the analysis results using five algorithms, such as K-mean and K-neighborhood, as a method to detect if there is a welding bead, and the experimental result proved that the proposed algorithm was the most accurate.

An Efficient Shadow Removal Technique adapted to Environmental Changes (환경변화에 적응하는 효율적인 그림자 제거 기법)

  • Ryu, Nam-Hoon;Ban, Kyeong-Jin;Oh, Kyeong-Sug;Kim, Eung-Kon
    • The Journal of the Korea institute of electronic communication sciences
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    • v.4 no.3
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    • pp.204-210
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    • 2009
  • There has been a lot of research into a background separation method, which is a preprocess of a technique of automatically perceiving an invader, and the removal of shadows around a moving object in the video monitoring field. When a moving object is not clearly separated from its shadow, it is difficult to analyze the shape accurately, and it is also hard to trace its position. This study suggests how to utilize a brightness value for removing a shadow. It came from the fact that there appears to be no change of color in the shadow area relative to the background area, and there only occurs a difference in brightness. In addition, this method uses the renewal of a critical value used for the removal of shadow in the previous frame, in the next frame.

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Reliability Assessment of Temperature Indicator for Simplified Measurement on Conservation Environment of Cultural Heritage (문화재 보존환경 간이 측정을 위한 온도지시카드 신뢰성 평가)

  • Lim, Bo-A;Shin, Eun-Jeong;Lee, Sun-Myung
    • 보존과학연구
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    • s.31
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    • pp.59-68
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    • 2010
  • Cultural heritages are damaged by surrounding several environmental factors. Main factors are temperature, humidity, light, atmosphere and indoor pollutant, organism, etc. Therefore, to prevent damage of cultural heritage from such environmental factor, conservation environment monitoring becomes more important. Indicator is one of the simple method for environment monitoring. It can be used without expensive and complex equipments. However, it should be performed scientific examination for application to cultural heritage. In this study, some Temperature Indicators were chosen and reliability assessment was carried out for application to cultural heritage. Brightness($L^*$) is selected for reliability assessment factor. As a result of lab test, Temperature Indicators were not influenced greatly in humidity change. When they were exposed to setting temperature, the color was changed in setting temperature area and ${\pm}2^{\circ}C$ part of setting temperature. Especially brightness value was high in setting temperature area. Also, Temperature Indicators were stabilized after about 16 minutes when were exposed to temperature difference of $10^{\circ}C$ and when temperature difference with exposure environment is smaller, stabilization time shortened. Therefore, it is a possible to confirm that selected Temperature Indicator is reliable product through measurement of color difference value and naked eye observation.

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4-channel Light Medical Therapy Apparatus for External Injury Cure (체외 상처 치유를 위한 4-채널 광 치료기)

  • Cheon, Min-Woo;Kim, Seong-Hwan;So, Keum-Young;Moon, Young-Lae;Mun, Seong-Pyo;Park, Yong-Pil;Lee, Ho-Sik;Kim, Tae-Gon
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.20 no.8
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    • pp.731-735
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    • 2007
  • We developed the 4channel Light Medical Therapy Apparatus for External Injury Cure using a high brightness LED. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity, frequency and so on, Especially, to control the light irradiation frequency, FPGA was used, and to control the change of output value, TLC5941 was used. Control stage is divided into 4 levels by program. Consequently, the current value could be controlled by the change of level in Continue Wave(CW) and the output of a high brightness LED could be controlled stage by stage. Compared with one LED irradiation, several LEDs irradiation could increase optical power.

EFFECTS OF FREENESS AND FILTER ON THE PHISICAL CHARACTERISTICS OF CIGARETTE PAPER (고해도와 충진제가 궐련지의 물리성에 미치는 영향)

  • Kim, Yeong-Ho;Seong, Yeong-Suk;Rhim, Kwang-Su
    • Journal of the Korean Society of Tobacco Science
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    • v.8 no.1
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    • pp.3-12
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    • 1986
  • Extensive studies have been made of the effects of freeness and the calcium carbonate on the physical properties of hand-sheets from commercial flax, kenaf and NBKP. As freeness increased, the hand-sheets from the pulps above showed higher retention rate of calcium carbonate, brightness, opacity and tensile strength but lower value of porosity. Among these, the retention rate(46%) showed the highest value In kenaf, the porosity(205 c.u.) in flax, and the opacity(67%) and the tensile strength(2.8kg) in NBKP respectively. Under the constant freeness, retention rate of calcium carbonate in hand-sheets increased until 1.4 times pulp weight was added in flax and kenaf but, in NBKP, decreased from the beginning of 0.8 times with the highest retention rate. Results above led to higher porosity, opacity, brightness but lowered tensile strength. Mixed pulp(Kenaf+ NBKP) showed higher retention rate than each pulp. Pictures of X-ray diffraction and scanning electron microscope demonstrated that both of domestic and foreign calcium carbonates were calcite of spindle form. The brightness of foreign calcium carbonate was higher by 295 than that of domestic one. The average particle size of calcium carbonate was 2.1 U m(domestic), 3.6 U m(foreign).

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Effect of the 100Hz PWM Low Power Light Irradiation in Proliferation of NTacSam:SD Bone-marrow Cell (NTacSam:SD 골수 세포의 증식에 100Hz PWM 저출력 광 조사가 미치는 효과)

  • Cheon, Min-Woo;Kim, Seong-Hwan;Lee, Ho-Sic;Park, Yong-Pil
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.04b
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    • pp.10-11
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    • 2008
  • We developed the equipment palpating cell proliferation using a high brightness LED. This equipment was fabricated using a micro-controller and a high brightness LED, and designed to enable us to control light irradiation time, intensity, frequency and so on. Especially, to control the light irradiation frequency, FPGA was used, and to control the change of output value, TLC5941 was used. Control stage is divided into 30 levels by program. Consequently, the current value could be controlled by the change of level in Continue Wave(CW) and Pulse Width Modulation(PWM), and the output of a high brightness LED could be controlled stage by stage. And then, each experiment was performed to irradiation group and non-irradiation group for bone marrow cells. MIT assay method was chosen to verify the cell increase of two groups and the effect of irradiation on cell proliferation was examined by measuring 590nm transmittance of ELISA reader. As a result, the cell increase of bone marrow cells was verified in irradiation group as compared to non-irradiation group.

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Analysis of Characteristic of Wound Therapy Apparatus using ${\mu}$-Controller (마이크로컨트롤러를 이용한 창상 치유기의 특성 평가)

  • Cheon, Min-Woo;Kim, Seong-Hwan;Park, Yong-Pil;Lee, Ho-Sik;Kim, Tae-Gon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.497-497
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    • 2007
  • We developed the light medical therapy apparatus for external injury cure using a ${\mu}$-controller. This equipment was fabricated by using a high brightness LEDs and a ATmega 128, and designed to enable us to control irradiation timer, intensity and reservation. Especially, to control the light irradiation frequency, and to control the change of output value, TLC5941 was used. Control stage is divided into 4 step by program. Consequently, the current value could be controlled by the change of level in Continue Wave(CW) and the output of a high brightness LEDs could be controlled, stage by stage. In this paper, the designed device was used to find out how a high brightness LEDs light source affects the skin wound of a small animal. In result, compared with none light irradiation animal, the lower incidence of inflammation and faster recovery was shown in light irradiation animal.

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